The figures, which show Britain's total population growing to 77.7 million, also indicate that the UK will become far less segregated as ethnic groups disperse throughout the country. In October, the Office for National Statistics predicted the population would exceed 70m by 2029.

Researchers found striking differences in the respective growth rates of the 16 ethnic groups studied. White British and Irish groups are expected to grow the most slowly, while the so-called other white group is projected to grow the fastest, driven by immigration from Europe, the US and Australasia. Traditional immigrant groups of south Asian origin (Indian, Pakistani and Bangladeshi) will also grow rapidly.

The initial findings of the three-year study include population projections for 352 local authorities in England, as well as projections for Wales, Scotland and Northern Ireland, for each year until 2051.

"The ethnic makeup of the UK's population is evolving significantly," said Professor Philip Rees of Leeds University. "Groups outside the white British majority are increasing in size and share, not just in the areas of initial migration, but throughout the country, and our projections suggest that this trend is set to continue through to 2051."

He added: "At a regional level, ethnic minorities will shift out of deprived inner-city areas to more affluent areas, which echoes the way white groups have migrated in the past. In particular black and Asian populations in the least deprived local authorities will increase significantly."

The research team investigated ethnic population trends at a local scale in the UK and built a computer model to project those trends under a variety of scenarios. They used existing data on the 16 ethnic groups recognised in the 2001 census, along with demographic factors such as immigration, emigration, fertility and mortality.

The research shows the white British population shrinking from 87.1% to 67.1% and the white Irish group shrinking from 2.5% to 2.1%. The other white group share grows from 2.5% to 9.9% – the greatest gain. Asian groups increase their share by three percentage points, black groups by two percentage points and Chinese and other ethnic groups by 2.6 percentage points.

The researchers said their data generated five different scenarios for population makeup for each year until 2051, with each of the five projections yielding different absolute figures for ethnic groups and the population size as a whole. This, they cautioned, highlighted the difficulty in predicting trends such as migration.

"It is impossible to predict exactly how people will move into, out of and within the country in the coming decades as all of these trends are influenced by a whole range of socio-economic factors," said Rees. "However, our results suggest that overall we can look forward to being not only a more diverse nation, but one that is far more spatially integrated than at present."

The immigration minister, Damian Green, said Britain had always benefited from being outward-looking and having a population with diverse backgrounds, but added: "Problems arise in periods when the population changes too fast for comfort. That's why the government wants to control the level of immigration so that we can benefit from the arrival of talented people from all over the world without putting pressure on our public services."